SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89772c5823ab35d4a546a418c9e65390a38376cf022b67f653ea9c40a50240e9' 
  AND token = 'Z4bTaC7yBxFX32q2kPREHUtG/UyWkG8p/jiPAE+bK4o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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