SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72754140b2cc5266d217ee154ca83ca668601bd74cb07fc270a649ffdc73f1c4' 
  AND token = 'W/pwzKn7TZqSQECoD5e1Z+qjL5CYlede0gwTByiUqn8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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