SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78260f5971a006467ed6d6d918767d6be996422bd6dabf2f425d3b99daf9c91f' 
  AND token = 'MIH3ZYUhDbL7TaB57l//JqwB1C2gPUGPbL7is8Smq+U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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