SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc44ead660fbc5dac313c24dc3ec884a76b02fbdd994b261d70298e11727e6c9' 
  AND token = 'bHAkdPxlKg6QaUeYztgtbewZJv6oMFO6O5OVipN2oM4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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