SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1c9f45d7184ebb87250639e8c4a30fdf4d1f4280f905598219d75d97e95bb32' 
  AND token = 'aBzq+vXbBYNlQKIJ/qUIHTAeG9v3djvPg1FpSxu5VVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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