SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '885db0e837cb104aa0abbad2886aa54b62887fbe1f16a3aab9fdb851272e853d' 
  AND token = '7v0LCBL6Ns5eoOA1norR0aQSMtYMULsoFB9bTrxczzo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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