SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2364576508e25f54297b1528065821e3d3206bd6d59aa23cf03bc2c797584940' 
  AND token = 'yZiByVsi4u7/Wo1eRlKvhmp6s+EU0l3FuOLQXt4DijY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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