SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '986660ddb05c1b160332663fcfb0d8ae0a4842f7da88859a990832758375774e' 
  AND token = '+q7pThlBj8rvWgdBP+zWu62gK2YuHIE3kf5IrOqpHlw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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