SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '158854df0426fb41566641a1985d19d7508d07bf204c0a7854a906e76c3875c4' 
  AND token = '6W2jP0Q+2CbAcJ/liNDZttZf1XTu81sAZxQEPXZ6D6k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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