SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7e71ff0c4644668ef7e4dc97339f8328754a382be474e1a51828179a491db64e' 
  AND token = 'dqi7kCJoejpgYLU3b0+va4CHdgvgmqaB+bYtFJsuxf8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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