SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e611e6bcf3f9d74b977a598855b74e95e4ddc943c0637f5f3dd4791c5ea3ee2f' 
  AND token = 'Zf5tR+GLWspQS4fkQYN6nSPyQ+mCJ11BC8Hagi1H7js=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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