SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7db0791ee1314330149325fc7af16b5ac262845c450e5f570308b6bbb18f3cf9' 
  AND token = 'ZJgN5moHCCvCJngNhAJ0GV4CMtEei/8dYPHjnznT2z4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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