Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c2a38f1df051f07629fd33d04705fce9a4e447499108566496574e6367069bf' 
  AND token = 'RZSrRlzLCr/ZYMt0zyTtAuaL+RfExBI8ZPATabG5Z44=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}