SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00a5297fc38295d4c64ad04a669037f4208d034e27c5d08463c0b4e94bf19e45' 
  AND token = 'Y64aasqoOKw61BfS4jQWPijOxzKvGPoyqouRQ0c/fsA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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