SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13d6eddbbb739257bae5c8a1d8ff075ba034db283398271449c938d9e6b881e1' 
  AND token = 'VDfqdjgixPRjVrtCa+NeylPQzmz8EamLt1p6bopZHTM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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