SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e476495959eb48ed20414c0c41405f3e1db7081f092998929ccb73182232b226' 
  AND token = '1bQZsQQ7rWREWz3hXJ0Ld+OGDqONNyPUuGikX4p9c78=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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