SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '147d7eb2f70ca2dada77da8be266119cca676a424f3171266fce173360ab5c7e' 
  AND token = 'JsKqsmR5V7VN/CXWaTSAdSXxPv4Vf/XOK4YRvQ/LhIg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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