SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd70589bc0961f8ea4ab52040764d55155ede93130c67beaa752fe75e241fb0c7' 
  AND token = '9ERYdLctT2Uh/uBybFaA9uGB1UXzwp5TiGh6YORt+sI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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