SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cdee2ecc12a005a653d87f6f347af5e7eb181ac83275efbd03410b66fe28db5c' 
  AND token = 'JW1vC7U6emlbPv9+I5756Xt2SqaUS8Seq3LA7/v0rmI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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