SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05d43135641e52c3180eaee841a4016b127054d90ba42b32094020d40acf168d' 
  AND token = 'PtT8oGwWTu3UIlDi+AW6WflWJB8TDuKpVToG8YVeERQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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