SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bf77a4e40ab2da3b78baefbd5932f5d7e8f229efc65ed40d0ad99f71dd938ac' 
  AND token = 'iC8WDCMHwarEB8JdH7uivRCfQ61/ur/4D6ksTyEQmbc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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