SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff77512b23929ed2c83f09bd6a9bf4e1abad717a3ed5b99f9c461467a62557d9' 
  AND token = 'PQCSVWcbA+S0OH9/zVnZrRedEgjRdJ/SB4KBilLRu3U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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