SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f12dc97e9a5144a7c1ccc8680340802f7e8338dad790b6160e2f3e21571dde56' 
  AND token = 'VGC69ISvuEhHNl//U9vzofLD1ANVUcNvmOIJoWCHrzE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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