SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77c72f6fde5cb277c150a92afd7089e5b245e8626064f206fd35b04ba2d96d4a' 
  AND token = 'vufDS1LkN5VElpLk3zerpaiwb0ORJ1zxCty5PXFNJQY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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