Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68f39730c6249bcadf6c6b79cefdc3fab19819412309f694d440e7baeb16df00' 
  AND token = 'RJz10FARaiGMlnLfnbqGxj5IHT94bPJkD1rxYngeVi0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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