SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c17a462cf16ae06b14569bde76dbd95944b50a13ac95dbedf0996a32f4f5216' 
  AND token = 'Qbl6uX9TfKx/dm0YV54VIsKJXnsGOrM3mZGqI09lWKs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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