SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11b0adbad72b85561ecb451c22338a64498b6af49838feaa10857a41ddbb9eac' 
  AND token = 'CfFh++G6Sl2jCqV3HOTSuWwZ9q46ILRui0M43+fal1g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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