SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61f6aaa4e5edd46a24a35559619ddf3402f17aca9ba528624e784008556ffb92' 
  AND token = 'CbwP0aTIoG6h3EHHbej0wH3tlNniNWQVyUKqKr0vSHQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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