SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6c12311bd643bf45eecdeb15f25113fe02dd503ef82bd28cc95355597a5ed3aa' 
  AND token = 'jtfnHdFcgMSJCUZvREMrjieLZKyvO9YMwnx1gz9onX0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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