SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b23eeabc17511bd7b7de777a8929d353660f106e854b4a785704fccdc9eaa4a' 
  AND token = 'inCfmxtqykpoLpbFNPk8DzRQaRE3PJjreONc/LUiKkU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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