SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9ef62f3ff3d42cc9e1c44ed60455006cebd169849fb471e6395516b54ecc49f' 
  AND token = 'hK782UGwj7AJ+m/Sja1J7aU7qTtHnWBoCLvrhCx7T58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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