SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b86aec7142843caa0c927439d5620dcd8afade37bbb80de35cb2aba8c927765a' 
  AND token = 'EMUt25JBSSF7rOwT4BI+oDBJo2Y7isg5V5h6aBJBREg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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