SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8955b97e00fbbb939dde7fdddeadcb39f69cab0f8e0bd792a7877bdf3e93e9e9' 
  AND token = '+vqKPYFJlQpzrGYx6dSuGJHoDS5hKW7ip6GB+DKvzhQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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