SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1375cfcb44ff432805d41677a1034e22b4e1abd5a1c582166b7a0906248c814' 
  AND token = 'cjOzFKd/qgSUIzPBw1/fE4wPjxT9qtjZkG9Do5TtIAA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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