SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2004b1822eafcc5f3089cdc38a84341fd35e228937c65bae73dceac649cd91a' 
  AND token = 'SncNO0308ShAZDVDHyVjLHYUZdt/LJXalAwUjBxA3Zo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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