SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9dcca3618e91ec9d08bbef0dc4367ecc618694b6312301b963aaf84963198f96' 
  AND token = 'mEczNWfFEBcXg7Zng4ABwcJSUQ84iA8RvJ9Yo26eTlw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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