SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84f3e73fea8ada551790f96eb08e82fe77afc2d8e4dc5022080315c1ffaa87e9' 
  AND token = 'Epwt+tjZxmpE7cP+6FojuO4/Xzb79ss0IDkdxs5TNBU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}