SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa00ab94c6f7f814b8f0844970233facd3ef3529285b2cc5320f1840fb69e99b' 
  AND token = 'DwKIpuLoWFCIVQuycXZXjg7spWBawYxG+PI45xkNaZA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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