SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '459798baec0bb24ff9370b2906d3f57b2901e002eac8e7cb1ceaac43bd8501cb' 
  AND token = 'eoQXGyGemkPw4Z9zpUhqvU5ZxcLhT8/+8yGKzDSmOqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}