SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd3e48f7df4d489766dacdbc70fe29766898e56645a182c6e98dcce844bd56125' 
  AND token = 'ZchVOhIU9D20bVcw/0a23Cf3Ub5iINfKnLKbNIuUq5c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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