SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a33d96caa461e3fcf2bd338c61289b1c4f10b5887a864c67b43b7374275b489' 
  AND token = 'XZMEpaFWYz5bBiqi3WoKiI+/7FBZhm3teAavj6Tv4VA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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