SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd5767c2cdf1848a0a3dcba50e2752f617faa415e5354eec7dd6124533a2efc9a' 
  AND token = 'PumbZ/VGtpodsZMVwrk/4qD9RwQssbYqDcYUyLnzuIc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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