SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e11025fd5f272c68048a6672162dfeca0c453adc25be30e86c4312049b46c174' 
  AND token = '34LaaAjj0/mnRakyHkmTel2khQ9wFK4uYQN6et8w5wA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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