SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45f32d2f4f3229d3344d7078822be32da306afa468233017ebd87a96b2c25291' 
  AND token = '6J++CU+LR8hNvGMVa1q7/Q4KuHUrgeFGjjstCfmThAU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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