SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07153b21a59f8446dceac239a4b560ee20193f4d2c41760ed0ec1c9ec57f267a' 
  AND token = 'MuRmYizu04e6+eGxxO1FqyzM+oOFs8gxuAFniVvtZlc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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