SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3508e4b86771dde7ffee475b18d1f7b96dd525581036073f098b6cf376c942c5' 
  AND token = 'ATrvBhM0Kc0Qn1GCfAVqtWbhLcRAM6QxfEmQTgs2Ogw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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