SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '704584fce63e81283329d2b94ba06610307da460d43797b68a0efe2a63094714' 
  AND token = 'ZWObW2a7CT7/FMTkq5JyRGgj1IQxFiix36lErnq0m7o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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