SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85e25874445028c6b3e1972447a31a39bf9ca17956a579d45bdff7235410f1e9' 
  AND token = 'OFG8gHCvFh0WzZIguNjiocHPicaLtot6/8RkPAuEinQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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