SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5451a236297db19623b6206ca925a15f0a2c7a4cbb5e7626da0dec67fd875da9' 
  AND token = 'jJHZ20y3ulqv4wpsF2EBGW2dQDTJdzhIyee0asHATo0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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