SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a9739dccb79fc0781b3afc075970041de0e3fe4fe25e8bbdc20d24dbb3f96e5' 
  AND token = 'wXnKf+TWSoJkRzgtXpJk3/Vv01QXVs+u5oCC44t9Jb0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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