SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd431128a526ca1e2804ebd222e19850ab087b9e698d0ccb4b98e4af76263c05' 
  AND token = 'hBZTCn4BL0bdnruLjSc3La47eDMwAeWfQeGfRjAN2Ds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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