SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '204e20e626ec84a036a812529e89dfcf098f4f2ee7a7debd44a997397ad70753' 
  AND token = 'ahb5gViKjUcG+PeJukdL561+fYcpnAti1/yQRlf5HoQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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