SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10f469e420807be1f6d257c20a9beae73a765d0e214c75dd06796ecceccef484' 
  AND token = 'ZKgV7YMAEOg7KrlvBgA+6prgydBBUZen6mMAY6Ku5jw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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