SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '196d1ff4606487faa750611ea6bb96c517f465db512c1191b9a83ea36ad031b1' 
  AND token = 's+MpmqWKwWhWvSibk4RmzPWHStyKSuMEd5moBr5p0lw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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