SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c786779ba30c8702fe13b6e1fe493ca42b43582beef4a56d1582cddd61567ee' 
  AND token = 'hZGAch6YQMvNA7VMuEoElsiBuN7+FIk2OTe8e5kpewU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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